code: def relu(grads):
      """Clips negative gradient values.
  
      Args:
          grads: A numpy array of grads to use.
  
      Returns:
          The rectified gradients.
      """
      grads[grads < 0.0] = 0.0
      return grads
  
file_path: keras-vis/vis/grad_modifiers.py
imports: from __future__ import absolute_import
  import numpy
  from keras import backend
  from .utils import utils
label_desc: Use image node_id 4 for calling a global function with example usage: relu(grads) and returns: grads